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Modern radar is a typical millisecond pulse load (MPL). Still, the independent power supply system of radar with a diesel generator (DG) as the main power source will have serious frequency fluctuation and voltage distortion problems. In practical applications, the main method to solve these problems is to increase the power supply capacity. This method will cause a serious waste of resources, and the mobility of the system will deteriorate. This paper takes the diesel generator with a millisecond pulse load system (DG_MPL) as the research object. It proposes a method to improve the power quality of DG_MPL by connecting the energy storage system (ESS) on the AC side. The system uses DG as the main power source and ESS as the auxiliary power source. The equivalent frequency regulation model is studied when the inverter control mode of ESS is selected PQ, Droop, and VSG, respectively. Finally, the system operating characteristics and power quality of several common improvement methods are compared and analyzed. The results prove that the proposed method can effectively improve the system frequency and voltage distortion problems.

We used molecular dynamics simulations to investigate the relationship between mechanical properties and deformation mechanisms in CoCrFeMnNi alloys having different compositions. According to deformation twinning activity, the deformation mechanisms in the different CoCrFeMnNi compositions under tensile loading can be classified into three major categories: easy-shear (ES), inter-locks (IL) and bulk hexagonal closed packed (hcp) transformation (BH). We found that the compositions with ES were more likely to rupture early because of the short and fragmented twins. The compositions following the IL pattern promoted the movement of interlocking stacking faults in the twin boundaries that could prolong tensile deformation. Moreover, BH could further increase ductility because the hcp transformation could absorb and dissipate the stacking faults. Experimental observations of immobile stacking-fault networks that impede dislocation motion and further provide preferred sites for the formation of the hcp phase were commonly found in the ES, IL and BH patterns. The calculated intrinsic stacking fault energies of CoCrFeMnNi and CoCrFeNi were consistent with the experimental measurements. The combination of high unstable stacking fault energy with the formation of the IL pattern results in high strength and high ductility in the CoCrFeMnNi HEA system.

It is generally believed that, in ghost imaging, there has to be a compromise between resolution and visibility. Here we propose and demonstrate an iterative filtered ghost imaging scheme whereby a super-resolution image of a grayscale object is achieved, while at the same time the signal-to-noise ratio (SNR) and visibility are greatly improved, without adding complexity. The dependence of the SNR, visibility, and resolution on the number of iterations is also investigated and discussed. Moreover, with the use of compressed sensing the sampling number can be reduced to less than 1% of the Nyquist limit, while maintaining image quality with a resolution that can exceed the Rayleigh diffraction bound by more than a factor of 10.

Billions of tons of keratin bio-wastes are generated by poultry industry annually but discarded that result in serious environmental pollution. Keratinase is a broad spectrum protease with the unique ability to degrade keratin, providing an eco-friendly way to convert keratin wastes to valuable amino acids. In this report, a feather-degrading thermophilic bacterium, Meiothermus taiwanensis WR-220, was investigated due to its ability to apparently complete feather decay at 65 °C in two days. By genomics, proteomics, and biochemical approaches, the extracellular heat-stable keratinase (MtaKer) from M. taiwanensis WR-220 was identified. The recombinant MtaKer (rMtaKer) possesses keratinolytic activities at temperatures ranging from 25 to 75 °C and pH from 4 to 11, with a maximum keratinolytic activity at 65 °C and pH 10. The phylogenetic and structural analysis revealed that MtaKer shares low sequence identity but high structural similarity with known keratinases. Accordingly, our findings have enabled the discovery of more keratinases from other extremophiles, Thermus and Deinococcus. Proteins encoded in the extremophiles shall be evolved to be functional in the extreme conditions. Hence, our study expands the current boundary of hunting keratinases that can tolerate extreme conditions for keratin wastes biorecycle and other industrial applications.

The new formulas for similarity measures between Vague sets will be used as pattern recognition method based on similarity measures in water quality evaluation. The application example shows that this method is not only convenient in calculation, but also practical in results.

According to the experimental analysis, this work found out the defect of the formula for similarity measure between current Vague values, and redefined the similarity measure between Vague values. Therefore, a new formula subject to the new definition was put forward according to data mining and uncertainty of Vague value.